Empty bottle bottom and neck inspection machine using radiation sensitive means



Dec. 10, 1968 R. G, HusoME 3,415,370

EMPTY BOTTLE BOTTOM AND NECK INSPECTION MACHINE USING RADATION SENSITIVEMEANS v med June s. 196e 4 sheets-sheet 1 14ML A l Jgar @LE/wv .Ms-OME,

J/wsume da A//s rmgwsyf Dec. l0, 1968 USING RADIATION SENSITIVE MEANS R.G. HUSOME EMPTY BOTTLE BOTTOM AND NECK INSPECTION MACHINE Filed June 3.1966 4 Sheets-Sheet 2 R. G. HUSOME EMPTY BOTTLE BOTTOM AND NECKINSPECTION MACHINE Dec. l0, 1968 USING RADIATION SENSITIVE MEANS 4Sheets-Sheet 5 Filed June 3. 1966 Dec. 1.0, 1968 R. cs. HusoME 3,415,370

EMPTY BOTTLE BOTTOM AND NEOK INSPECTION MACHINE USING RADIATIONsENsITIvE MEANS Filed June 3. 1966 4 Sheets-Sheet 4 OO n.9. n

45rd f ,Livre/vra@ 05597 G2. EMM HSOME, I

United States Patent 3,415 370 EMPTY BOTTLE BOTTOVI AND NECK INSPEC-TION MACHINE USING RADIATION SENSI- T-IVE MEANS Robert Glenn Husome, ElSegundo, Calif., assgnor to San Marino Electronic Corporation, ElSegundo, Calif., a corporation of California Continuation-impart ofapplication Ser. No. 504,471, Oct. 24, 1965. This application June 3,1966, Ser. No. 555,148

17 Claims. (Cl. 209-1113) This application is a continuation-in-partapplication of my co-pending application, Ser. No. 504,471, tiled Oct..24. 1965 for Empty Bottle Bottom and Neck Inspection Machine, nowabandoned. Ser. No. 504,471 is, in turn, a continuation-in-part of myapplication Ser. No. 230,345 led Oct. 15, 1962 for Empty BottleInspection Machine, now abandoned.

This invention relates to apparatus for inspecting empty bottles forforeign matter and, more particularly to irnprovements in the detectionportion of such apparatus.

The construction of a successful bottle inspection machine has long beena desired goal. To .properly inspect empty bottles for foreign matterpresents many problems which have heretofore not been satisfactorilysolved. The prior art systems for inspecting empty bottles have cornplexand bulky scanning systems. The systems in the prior art are, because oftheir complexity and bulk, quite unreliable. Further the prior artsystems inspect only a small part of the entire volume of the bottle;they inspect primarily for foreign matter located at the bottom of thebottle to be inspected.

Accordingly, it is an object of this invention to provide a novel andimproved detection system for an empty bottle cleanliness inspectionmachine.

Another object of this invention is to provide for empty bottleinspection machines, a detection system which is reliable and requireslittle maintenance and repair.

A further object of this invention is to provide a detection system foran empty bottle inspection machine, which detection system has anautomatic adjustment to accommodate bottles of varying opacity.

Another object of this invention is to provide a detection system for anempty bottle inspection machine, which system detects foreign matter insubstantially the entire volume of a bottle where foreign matter islikely to occur.

Yet another object of this invention is to provide a detection system ofthe character described which is capable of detecting foreign matter ina bottle despite a predetermined relatively high level or irregularityin the light transmission characteristics of the glass in the bottlesbeing inspected.

Another object of this invention is to provide a detection system of thecharacter described which is efficient to manufacture.

The present invention, in its presently preferred embodiment, providesan empty bottle detection system, in which a bottle to be inspectedpasses through an inspection station. Provided in the inspection stationis a light source which 4directs light from a point below the bottlethrough the bottle bottom. Above the bottle is a light collecting andreflecting optical system. The system is so arranged as to opticallyview each bottle as it passes through the inspection station. Light fromthe light source passes upwardly through the bottom of the bottle,thence through a lens which focuses an image of the bottle bottom, theimage hereby formed is focused upon a rotating mirror disposedthereabove. The mirror includes a reflecting line or segment upon a darkbackground and thus during rotation of the mirror, light from successiveareas of the bottle image are compared and ultimately discriminated. The

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light reflected from the mirror is directed to a photocell which readsout the light received. Thus, as each bottle is scanned at theinspection station, a bottle including foreign matter on its bottom orin the vicinity thereof causes a time dependent change in the .amount oflight falling on the photocell, thus producing a signal which actuates amechanism (hereinafter described) to remove the bottle as a reject.

The rotating mirror is preferably concave and is of such a design and isplaced with respect to the bottle so that the mirror focuses an image ofthe top of the bottle onto an image plane. The photocell is placed inthis image plane and means are provided lto scan this image by a wobblemotion of the mirror. Thus, the light through a bottle being scannedwhich has foreign matter in the vicinity of its top also causes a timedependent change in the amount of light on the photocell and the bottlewill thus be rejected.

Although the same photocell is used for rejecting the bottle for foreignmatter in the top as well as the bottom thereof, it is seen that twoscanning phases take place, that of the top of the bottle and that ofthe bottom. Because of the great depth of focus (hereinafter explained)achieved by the present invention optical system, this twophase scanningsystem detects foreign matter in substantially the entire volume of thebottle.

The novel features which are believed to be characteristic of theinvention, both as to its organization and method of operation, togetherwith further objects and advantages thereof, will be better understoodfrom the following description considered in connection with theaccompanying drawing in which a presently preferred embodiment of theinvention is illustrated by 'way of example. lIt is to be expresslyunderstood, however, that the drawing is for the purpose of illustrationand description only, and is not intended as a definition of the limitsof the invention.

In the drawings:

FIG. 1 is a ifront elevation, partly in section, showing the presentinvention apparatus in its preferred embodiment; Y

FIG. 2 is a partial sectional view taken along line 2--2 of FIG. 1;

FIG. 3 is a view taken along line 3 3 of FIG. 1;

FIG. 4 is a View, somewhat enlarged, taken along line 4-4 of FIG. 1;

FIG. 5 is a bloc-k diagram of one circuitry system used in the detectionsystem of the apparatus of FIG. 1;

FIG. 6 is a block diagram of another circuitry system used in thedetection system of the apparatus;

FIG. 7 is a graphic pilot showing the light sign-a1 intensity as afunction of time established :at the scanner photocell of FIG. l;

FIG. 8 is a schematic View showing the light ray pattern of the presentinvention optical system in its presently preferred embodiment;

FIG. 9 is a partial view taken along line 9--9 of FIG. 1;

FIG. 10 is a schematic view showing graphically the scanning actionaccomplished by the offset axis of the ap'- paratus in FIG. 1 and shownin FIG. 8;

FIG. l1 is a schematic view showing graphically the effective use of thelens aperture of the apparatus of FIG. 1 employing the system of FIG. 5;

FIG. 12 is a schematic view showing graphically the effective use ofthe' lens aperture of the apparatus of FIG. l employing the system ofFIG. 6; and

FIG. 13 is a somewhat enlarged view of the face of surface 32. havingthereupon a reflecting segment different from that shown in FIG. 4 as analternative thereto.

Referring now to the drawings, there is shown a bottle 10 in the teststation position. The bottle is transported through the test station byparallel star wheels 12 and 14 which overhang a conveyor, all in amanner and of a construction well known in the art. This portion of thepresent invention apparatus is shown in United States Patent No.2,800,226. The star Wheels 12 and 14 are supported by rotor 16 to bedriven. The shaft or rotor 16 may be externally driven to thus rotatethe star wheels or it, in turn, may be driven by the star wheels in afree wheeling mode of operation. The latter mode of operation may beeffected by movement of the bottles through the test station by aIbottle conveyor not forming a part of this invention. Near the `bottomstar wheel 14, and in association with each pocket therein, not shown,there is provided a vacuum operated suction -cup 20. The suction cup 20is adapted to secure and remove a bottle to be rejected in a mannerhereinafter to be'described.

In operation a bottle 10 in the lfree wheeling mode is moved into thetest station by the conveyor, not shown. The bottle is held in theupright test position as shown in FIG. 1 over a diffused glass plate 22.Located near the upper and lower ends of the bottles, at heightsapproximately the same as those of the star wheels 12 and 14, is -a pairof spring guide members 95 and 96. Their construction may better be seenin PIG. 9. Each of these members includes a pair of vertically supportedpulleys 97 and 98 about which is disposed a wound construction springmember 99. Below the diffused glass plate 22 is a light source 25. Thelight from source 25 passes up through the glass plate 22 and throughthe bottle 10 to the focusing lens 30. Above the lens is a concavesurface 32 which is obliquely supported by the shaft of motor 34, asshown in FIG. 1 and schematically indicated in FIG. 8.

The lens 30 focuses the image of the bottom ofthe bottle in theinspection station upon the surface 32 which has there-on a mirrorsegment 50; the remaining surface of the surface 32 is non-reflecting asindicated in FIG. 4. The mirror segment 50, therefore, at all times seesa portion of the image of the bottom of the bottle. This portion rotatessince the mirror segment 50 directs by reflection the light thereupon tothe scanner photocell 35. Photocell 35, to avoid confusion in thedrawing, is not shown in FIG. 1. It is shown in FIG. 8 wherein there isa rotation of 90 in the FIG. 8 relative to FIG. 1 in order to clearlyshow cell 35 and another photocell 113 later to be discussed. Since theimage of the bottom of the bottle is focused upon mirror 50 and sincethe mirror 50 is concave and thus h-as a focal length as does a lens,the mirror 50 collects the light it receives and directs it toward thephotocell. Thus, when mirror 50 during the course of its rotationintercepts an image of a portion of the bottle bottom with a foreignmatter particle therein or thereon, the light reflected toward thephotocell 35 from mirror 50` will be of reduced intensity (-because ofthe presence of the foreign particle).

As stated hereinabove, surface 32 is concave and, therefore, mirrorsegment 50 which is upon surface 32 is a concave mirror and thus willlfocus images as will a lens. The detection system is so arranged andconstructed that photocell 35 is placed in an image plane of mirror 50which image plane is the plane at which an image of lens 30 will befocused by mirror 50. Stated differently, by this optical arrangement animage of the lens 30 is focused onto the surface of the photocell 35,concomitantly the image of the bottom of the bottle is not focused ontothe surface of the photocell 35. This construction is readily achievedby using a predetermined mirror concavity, and photocell to mirrordistance and lens to mirror distance, all of which are easily calculatedby methods well known in the optics art. The concavity of mirror 50 andthe photocell 35 to mirror 50 distance will not adversely afrfect thedetection in the vicinity of the bottom of the bottle. That is, toprovide the proper optical structure, it is necessary to place lens 30at the focal plane of mirror 50Also, the mirror 50 must be 'located atthe focal plane of lens 30 so that the bottom of thel bottle will befocused by lens 30 on the mirror surface 50. This is easily achieved,when it is recognized that photocell 35 need not be at a focal length oflens 30 since the image of the bottom of the bottle need not and indeedshould not be in focus on the photocell but need only be in focus uponsurface 32.

Thus, be'the arrangement hereinabove described, lens 30 is focused bymirror 50 onto photocell 35 and thus photocell 35 sees an image of lens30 and will see foreign matter in the vicinity thereof (and near theneck of the bottle). In FIG. 1 the distance between the bottom of lens30 and the top of the neck of the bottle is greatly exaggerated; they,in fact, in order to accomplish the above, are placed as close togetheras is practically possible (which is shown more accurately in FIG. 8).As will be described hereinbelow in greater detail, the photocell 35scans the top region of the bottle.

It is possible, of course, to observe and inspect the bottom and topregions of the bottle by utilizing two sensors instead of one; however,this makes the unit less reliable and more complex and more difficult tocalibrate accurately.

The present invention optical system with its double focusing system maybe best understood with reference Vto FIG. 8, wherein the focusing ofthe images is schematically shown.

The light rays passing upwardly from the bottom of the bottle passthrough lens 30 and are focused by lens 30 onto surface 32. This is seenby rays a, b and c which emanate from one point and which are focused bylens 30 to a single point on surface 32. Rays d, e and f are similarlyfocused by lens 30 onto surface 32. As mirror segment 50 sweeps acomplete revolution as schematically represented in FIG. 8, rays a, band c will be defocused by'mirror 50 and be reflected to the surface ofphotocell 35. A second photocell 113 is positioned adjacent to photocell35 as is shown in FIGS. 8 and l1 for the purpose hereinafter to beexplained. If the portion of the image of the bottom that mirror 50 seesat any instant has a particle of foreign matter therein, the lightintensi ty reflected to the photocell will be momentarily substantiallyreduced; this change in light intensity can be detected and used toactuate the rejection system hereafter described. The change ismomentary because of the rotation of mirror 50 and the change will besubstantial because as can be seen in FIG. 4, the ratio of the area ofmirror segment 50 to the area of surface 32 is quite low. The rotationrate of mirror 50 in the presently preferred embodiment is 12,000 r.p.m.This is one revolu- 1 tion per 5 milleseconds and corresponds to a scanrate of 200 c.p.s. Thus the bottom of the bottle is scanned at a rate of200 times per second.

The image of the aperture of lens 30 is focused by mirror 50 ontophotocell 35. As can be seen in FIG. 8, rays a, d which emanate from asingle point on lens 30 are, therefore, focused as a single point in thevicinity of photocells 3S and 113. Similarly focused are ray pairs b, e,and c, f.

The detection system operates on the rate of change of intensity oflight resulting when a particle of foreign matter is encountered in thecourse of scanning the bottle.

In order to provide a scanning of the region in the top of bottle 10,means are provided to effectively scan the top region to give an effectwhich is equivalent to that from scanning the bottom of the bottle byrotating mirror 50. The top region of the bottle is scanned by orbitingthe image on photocell 35. To achieve this the optical and rotating axisof surface 32 and mirror 50 are displaced as can be noted in FIG. 8. Therotational axis of C is laterally displaced from the center or opticalaxis A so that with respect to photocell 35, the surface 32 and mirror50 wobble. Thus, the image of the aperture of lens 30 which is focusedby mirror 50 onto photocell 35 wobbles with respect to photocell 35. Ascan be seen in FIG. l1, the image of the lens aperture is much largerthan the viewing area of photocell 35. It can, therefore, be readilyseen that if mirror 50 did not wobble, photocell would observe only afixed area of the image of the top of the bottle and would not see themomentary change in light intensity necessary to actuate the rejectmechanism in all situations. For example, if a line object such as a pinwere caught in the neck of the bottle the photocell 35 would see it atall times were it not for the wobble and thus not indicate that foreignmatter was there present. However, with the wobble effect as shownschematically in FIG. l0, the image of the line object would wobble onand off of photocell 35 and thus produce the proper signal for rejectionof a bottle which has foreign matter in the neck region. The wobbleeffec-t can be accomplished by displacing axis C as describedhereinabove and `shown in FIG. 8, or exactly the same result is achievedby tilting the mirror on its rotational axis. The amount of displacementin the presently preferred embodiment is of the order of the O D. ofphotocell 35 Ias may be seen in FIG. 10. A typical O.D. for thephotocell is 1/8 inch.

Thus, it is seen that by this novel optical and mechanical structure,both the top and bottom regions of bottle 10 are inspected for thepresence of foreign matter. As is well known in the optics art, theeffective f stop of the system described herein can be very small. Asmall aperture gives a correspondingly high depth of focus, so that inactual operation of the detection system, foreign matter can be detectednot only at the bottom of the bottle but in a region substantiallythereabove. Further, because lens 30 is very close to the top of bottle10, approximately within 1A; inch, the detection at the top of thebottle 10 extends throughout the entire neck region due to the greatdepth of focus. Thus, the detection takes place in substantially theentire volume of the bottle in which foreign mat-ter is likely to occur.

Referring again to FIG. l, mounted alongside lens 30 and on an axisparallel thereto is a shaft 40. The shaft rotatably carries a turnstilewheel 41 which engages the neck of the bottle being inspected. The wheel41 is designed so that the pockets defined thereby serve to nest thebottles in such a position that the axis of the bottle is on a p-arallelline with the axis of the wheel and the edge of the bottle makingcontact with the side 43 of the Wheel is such that a line tangentthereto is lparallel to a diameter of the wheel. A wheel 42 mounted onthe opposite end of the shaft 40 is opaque to light except for theprovision of equally spaced transparent openings 45 placed atpredetermined angular intervals as shown in FIGURE 3. These openings areat angular positions on the wheel which corresponds to the position ofthe neck of the bottle 10 as it is seated within the pocket of the wheel41. Just below the wheel 42 there is disposed a small light source 46which is in the line of the openings 45. Just above the light source 46and above the wheel 42 is mounted a turns-tile `photocell 48. The entireinspection head structure which includes the surface 32 and mirrorsegment 50,. lens 30, cells 35 and 48 and associated elements isarranged to be raised and lowered in accordance with the height of thebottles to be inspected.

In FIG. 4, there is shown the reflecting segment 50 which is a portionof the surface 32, which surface except for segment 50 isnon-reflecting. In the presently preferred embodiment of this invention,segment 50 is refiecting and surface 32 generally non-reliecting. It isalso possible to have segment 50 non-retiecting and surface 32 generallyreiiecting.

Referring now to FIG. 5, it will be seen that the output signal from thescanner cell 35 is fed to an amplifier 55 of conventional design. Theoutput signal from cell 35 consists of a steady state component m and anon-steady state component q. The component m corresponds to the averagelight transmission of the bottle. It is a function of the opacity of thebottle. The non-steady state component q results from the changeeffected on the light intensity which change derives from foreign matterbeing present in the bottle and also from contrasting areas in thebottle such as lettering imprinted in the glass and imperfections in theglass. Part of the component q also results from the bottle being movedthrough the inspection station as it is being scanned. Since thecomponent q results from changes in contrast during scanning, itsamplitude is dependent on the opacity of the Ibottle also. That is, lesssignal change will result from a foreign particle lying in a dark bottlethan would in a light bottle. The cell 35 is of the silicon photovoltaictype; however, any type of photocell including photoresistive types maybe used. The photovoltaic cell was chosen in the embodiment associatedwith FIG. 5 because of its wide spectral response and rapid response.The cell 35 can be used successfully with most bottles that arepresently in commercial use in liquid bottling plants.

The output of A.C. amplifier 55 (of conventional design) at point 121will be the component q multiplied by the gain of amplifier 55 anddivided by the voltage divider formed by resistor and the impedance ofthe AGC cell 111.

Photocell 111 is provided as a means to automatically compensate forlight changes which are primarily due to differences in opacity frombottle to bottle. Cell 111 is located above lens 30 on bracket 21.Because of its location, cell 111 sees light emanating from the bottomof the bottle and also light emanating from the walls of the bottle,thus the parameters of cell 111 will be dependent upon the average lightemanating from the bottle. If the light emanating from the bottlevaries, the impedance of cell 111 also varies and thus changes thevoltage output at point 121. By proper selection of photocell 111 andresistor 115 by methods well known in the art, the cell 111 serves as anautomatic compensation control such that detection will be equallyefficient and accurate in bottles of widely varying opacity.

It is readily seen from the inclusion of a capacitors 116 and 117 in thecircuit that all electronic operations on the signal from scanner cell35 are on the non-steady state signal component q alone. The output frompoint 121 which is light compensated is then fed into A.C. amplifier 66(of conventional design) for further amplification. The output ofamplifier 66 is then fed into a conventional differentiation circuit 68so that the output signal appearing at terminal 69 is proportional tothe slope of the signal received at the terminal 67. Thus, the magnitudeof the signal appearing at terminal 69 represents the abruptness ofchange of the light signal passing through the bottle as received by thescanner photocell.

The output of the dierentiation circuit 68 is fed to pickoff amplifier70. Amplifier 70 is a high gain-differential amplifier of a kind wellknown in the art.

A potentiometer 60 connected to a source of voltage E is adjusted toproduce a predetermined voltage which is a function of the lighttransmission characteristics of the particular run of bottles beingtested. Thus, the potentiometer is designed in FIG. 5 as the darknesssensitivity control. The voltage produced by potentiometer 60` providesa reference voltage into pickofi amplifier 56 which is an amplier of thesame type as amplifier 70. The reference voltage is compared by means ofamplifier 56 to the D.C. voltage produced by photocell 113. Photocell113 receives the light from mirror 50 as does photocell 35. Photocell113 serves to generate a D.C. voltage representative of the light levelpassing through the bottom and neck of bottle 10. The output ofphotocell 113 is fed tol one of the inputs of differential amplifier 56.Photocell 113 in the presently preferred embodiment is of thephotoresistive type cadmium selenide, chosen for its capabilities ofhigh output. Other photocells can also be used with proper adaptation ofcircuitry. Thus, amplifier 56 produces an output signal which depends onthe differential between the outputs from potentiometer 60 and photocell113. Photocell 113 is placed next to scanner cell and thus sees the samething as cell 35, i.e., the light refiected from mirror segment 5f)which is derived from the light passing through the bottom of the bottlebeing inspected. The output of amplifier 56 is thus an indication of theopacity of the bottom of the inspected bottle. The signal is, therefore,utilized as described hereinafter, to determine whether the bottle isunacceptable because the bottom of the bottle is sufficiently dark thateither it is heavily covered with foreign matter in a uniform manner oris so dark itself that foreign matter therein cannot be detected; thesame will also indicate that the neck of the bottle is obscured as by alarge object within the bottle or a cap on it.

Normally the voltage established by the potentiometer 60 is lower thanthat of the signal anticipated at the input of the amplifier 56. If itis assumed that this amplifier has sufficient gain, it will thus bedriven into negative saturation. When the bottle under inspection is sodark and opaque as to be unacceptable (i.e., foreign matter containedtherein could not be detected), the signal at the input of the amplifier56 is less than the voltage established by the potentiometer 60; thus,the pick-off amplifier will be driven into positive saturation and anoutput signal will appear at the output terminal 75 of or gate 62. Gate62 is an or gate of conventional design which is adapted to produce anoutput signal if there is a signal of a predetermined level establishedat either of -its input terminals 61 or 63.

As described hereinabove, the differential signal at terminal 69 is fedto amplifier 70'. Also fed into amplifier 70 as in amplifier 56, is apredetenmined reference voltage which is the contrast sensitivityvoltage established by potentiometer 72 at terminal 73.

Whenever the signal at 69 is greater than the voltage at 73, assumingamplifier 70 has sufficient gain, this amplifier will be driven topositive saturation and a predetermined positive voltage will appear onterminal 63 at the input of or gate 62. As previously mentioned,whenever an input signal appears at either input terminal 61 or `63 ofor gate 62, there will appear an output signal therefrom at its outputterminal 75. The output signal at terminal 75 feeds a conventional andgate 82 which is adapted to produce a signal at its output terminal 83only when signals are present at both of its input terminals, namely, 75and 81.

The turnstile photocell 48 is energized for a period of time which is afunction of the velocity of the bottle in the inspection station as itmoves a predetermined distance, preferably 1A; inch. This isaccomplished by providing openings 45 within the wheel 42 of thepredetermined s1ze.

T'he wheel 42 is caused to rotate by movement of the bottle through theinspection station. Thus, a signal will appear at the output terminal 49of the photocell 48 during the time the bottle moves a predetermineddistance.

This time interval is not fixed. It is a function of the speed of thebottles. The positioning of the wheel 42, the turnstile photocell 48,and light 46 is such that the cell 48 receives light just before,during, and just after the time that the bottle under inspection iscentered on the optical axis of lens 30.

The output signal at terminal 49 from the turnstile photocell 48 drivesa Schmitt trigger circuit 80 which produces a square wave output signalat terminal 81. The leading and trailing edge of this square wave signalcorresponds to the bottle position li before and ls" past the opticalaxis of lens 30.

The concurrence of signals at terminals 75 and 81 will produce an outputsignal at terminal l83 as this is the condition required to generate asignal by and gate 82. An output signal from and gate 82, in turn servesto trigger relay driver 86 which may be a conventional one shotmultivibrator. Thus, a pulse of a fixed amplitude and duration will bepresented at a terminal 87 to actuate relay 90. Relay 90 serves to closethe circuit to a r` reject solenoid not shown, associated with thevacuum line leading to the suction cups previously mentioned.

The suction cup 20 shown in FIG. l will thus receive a vacuum through anopening connected through a passageway 101 to a vacuum pump, not shown.A valve 103 is shown in the reject position permitting the vacuum tosecure the bottle to the cup. After the reject solenoid has driven thevalve 103 into the position shown, it will remain in this position untilthe valve plate and associated star wheels have rotated a fixed numberof degrees, and delivered the reject bottle to the ejection position. Atthis point, the depressed valve contacts a claw-shaped reset cam, notshown. The `mushroom head of the valve spool is retracted to its normalposition by cam action as the valve plate continues to rotate, whichopens the passageway 100 to the atmosphere. All of this portion of thereject mechanism is well known in the art.

Reference is again made to FIG. 8 in order to further explain thepresent invention optical system. Assuming no pattern on reflectingsegment 50 on the face of the surface 32, whether rotating or not, andassuming that the bottle being inspected has a homogenous bottom withoutnomenclature, and no foreign matter in the bottle, a steady state lightbeam of a predetermined intensity will be seen by the photocell 35. Thisin turn will result in no signal at the output of amplifier 55. Notethat as the photocell is smaller than the lens aperture, it will seeonly a portion of the light (presumably at the center) passing throughthe focusing lens 30. If, however, a particle of foreign matter appearsin segment 50 when it is not rotating, the light intensity reaching thephotocell will be of a steady state at a level less than that absent theparticle of foreign Vmatter as now less light reaches the mirror. If themirror is now rotated, the reduced light intensity seen by the photocellwill be further reduced on each revolution during the instant in timewhen there is a coincidence in the position of the refiecting segment 50with the image of the particle of foreign matter as seen by the mirror;this lessening of light intensity serves momentarily to decrease thelight intensity seen by the photocell and produce the non-steady state qcomponent signal. It will at once be apparent that other opticalirregularities, such as inconsistencies in the light transmissioncharacteristics over the bottom of the bottle and other factorspreviously mentioned, will further contribute to the component q.

In FIG. 8 there are shown two axes for the spherical surface 32, onebeing the optical axis A and the other a rotational axis C. While bothaxes, in the simplest embodiment are coincident, in the presentlypreferred embodiment they are displaced as shown. The displacement willtypically be about the same as the radius of the photocell 35, i.e.,approximately ls. With this displacement there will be a wobble ororbitting. The portion of the lens aperture viewed by the photocell willthen effectively be a circle 31 having as its radius the diameter of thephotocell 35 (see FIG. 10). This results in a motion which effectivelyacts as if the photocell were rotated about the axis of the aperture oflens 30` (shown greatly enlarged in FIG. 10. This serves to have thephotocell view a line object which may be lodged in the neck of thebottle, that is, in the upper third thereof outside of the viewing rangeof the system absent the orbiting mode here described. This is due tothe fact that there will be a time dependent change in light intensityreaching the photocell each time the photocell effectively passes overthe line object constituting an article of foreign matter within theneck of the bottle and thus produce a non-steady state signal of thesame kind as would be produced through scanning of the bottle bottom byrotation of segment 50.

As has previously been mentioned, it is important to have the bottlemove during the inspection cycle, only in order to detect a discreteparticle which is directly centered within or near the bottom of thebottle. If this is not done, the reflective segment 50 of the rotatingsurface 32 would never scan the image of this particle, and no timedependent change in light intensity would reach the photocell.

Referring to FIG. 4, reflective segment 50 is made progressively widertowards the center of surface 32 faccording to a predetermined curve.This widening is done to provide linear response for scanning particlesin different areas of the bottom of the bottle. The scanning area iscircular, and thus particles at the periphery will be seen for a shortertime duration than particles at the center, thus producing a more abruptchange which will be differentiated by circuit 68. To achievelinearityin the output of circuit 68, segment 50 is tailored to produce largeamplitude pulses upon scanning of particles located towards the centerof the bottle so that the differentiated sign-al out of circuit 68 willbe of the same peak amplitude as when peripheral particles are scanned.

Reference is now made to FIGS. `6 and 12 which may be said to provide analternate embodiment of a circuit and optical system to be used inconjunction with the apparatus of FIG. l. In this embodiment the circuitand optics are essentially the same in construction and operation as wasshown and described in connection with FIGS. and 1l. The onlydifferences .are as follows: Tlhe D.C. photocell 113 of FIG. 5 and 1l isdeleted, In addition, the A.C. amplifier 50 of FIG. 5 is replaced by aD.C. amplifier 150 of conventional design. Further, the pickoffamplifier 56 receives its signal in the FIG. 6 embodiment directly fromthe D.C. amplifier 150 instead of from the D.C. photocell 113 of theFIG. 5 embodiment.

The operation of the FIG. 6 circuit is essentially the same as thatdescribed in connection with FIGS. 5 and l1 with the followingmodifications: The scanner photocell 35 is selected to have thecharacteristics whereby its response time and signal sensitivity areboth sufficient,- ly high to enable it to sense the level of lightpassing through the bottle and the rapid changes q in light level whichoccur when scanning foreign particles as small as ls in diameter. TheD.C. amplifier 150 amplifies both of these components of this signal.The output from amplifier 150 is applied to the pick-off amplifier 56and to the capacitor 116. The D.C. light level component is Ifed toamplifier 56 and serves to generate a D.C. voltage representative of thelight level passing through the bottom and neck of the bottle 10. Thepulse or q component is fed to A.C. amplifier 66 via capacitor 116,resistor 115 and capacitor 117, all serving the same purpose asdiscussed in connection with FIG. 5. Thus this is a simplified system,eliminating one photocell and thus making the system simpler and morereliable.

In the presently preferred embodiment the reflecting mirror segment 50preferably extends from the center to the edge of the rotating surface32. Nea-r the edge it assumes a line shape of a narrow width preferablyof the order of 1/32". The under portion near and at the center ispreferably 1/s, all of this from a su-rface 32 of 2 in diameter. Thus itis seen that the ratio of the area of the nonreflecting to thereflecting surface portion of surface 32 is large, i.e. of the order of50:1. This is determined by determining the area of the segment S0 byassuming it approaches a rigid triangle l x 1/a" having an area of 1/15square inch. The total area is 1r 1:3.14 square inches. Further, thepresent invention resides not only in providing a large ratio asdescribed above wherein the maximum width of the segment should be nogreater than the O.D. of the smallest particle to be detected; herein1A" is assumed. Additionally, whether one reflecting or severalreflecting areas are employed, it is preferable to have them constitutea small portion of the total area, i.e., of the order of less than 1/10.This has been -found to substantially improve the system detectioncapability and especially the signal to noise ratio.

Another variation in the present invention optical system which may beused within the spirit and scope of the invention is to substitute arotating plano convex lens with a fiat mirror surface to direct thelight from the bottle tothe photocell 35.

There has thus been described a new and improved empty bottle inspectiondetection system of improved design. It will then be understood thatvarious modifications may be made without departing from the spirit ofthe invention. For example, several mirrored segments may be employed inplace of the one segment 50 located upon surface 32. In addition, theshape of such segment may be altered to compensate for the difference-inthe tangential velocity of eaoh point on the line as it extendsoutwardly from the center of the mirror. Another technique forcompensating for this differing speed may be by the use of variableintensity filters or by varying the reflectivity of the segment alongits radial dimension.

What is claimed is: v

1. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign matter within a bottle, said detectionsystem comprising:

(a) means for directing radiant energy through a bottle;

(b) means for focusing from said radiant energy an image of the bottomof said bottle;

(c) a rotating surface having thereon a reflective segment, said surfacebeing concave and located in the image plane of said bottom of saidbottle as focused by said focusing means;

(d) said reflective segment being arranged to scan said image of saidbottom of .said bottle during rotation of said surface;

(e) a radiant energy sensor, said sensor being disposed in the path ofradiant energy` reflected from said segment, whereby the amount of saidenergy received by said segment is momentarily substantially variedWhenever said segment in the course of rotation thereof coincides withthe image of a particle of foreign matter disposed in said bottleproximate the bottom thereof;

(f) said rotating surface having a predetermined concavity and beingarranged so that the area proximate the neck of said bottle is focusedbyjsaid reflective segment on said surface to an image plane;

(g) said radiant energy sensor being located in said image plane of saidbottle neck;

(h) means for scanning said bottle neck image by said sensor whereby theamount of radiant energy received by said sensor is momentarilysubstantially varied whenever said sensor in the course of scanningcoincides with the image of a particle of foreign matter disposed insaid bottle neck;

(i) circuit means for producing an output signal indieating thecondition of said sensor; and

(j) means responsive to said output signal for rejecting a bottle fromsaid inspection machine whereby when said output signal indicates thepresence of foreign matter, the bottle is rejected.

2. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign matter within a bottle, said detectionsystem comprising:

(a) means for directing radiant energy through a bottle;

(b) means for focusing from said radiant energy an image of the bottomof said bottle;

(c) a rotating surface having thereon a reflective segment, said surfacebeing concave and located in the image plane of said bottom of saidbottle as focused by said focusing means;

(d) said reflective segment being arranged to scan said image of saidbottom of said bottle during rotation of said surface;

(e) a first radiant energy sensor, said sensor being disposed in thepath of radiant energy reflected from said segment, whereby the amountof said energy received by said segment is momentarily substantiallyvaried whenever said segment in the course of rotation thereof coincideswith the image of a particle of foreign matter disposed in said bottleproximate the bottom thereof;

(f) said rotating surface having a predetermined concavity `and beingarranged so that the area proximate the-neck of said bottle is focusedby said refiective segment on said surface to an image plane;

(g) a second radiant energy sensor being located in said image plane ofIsaid bottle neck;

(h) means for scanning said bottle neck image by said second sensorwhereby the amount of radiant energy received by said second sensor ismomentarily substantially varied whenever said second sensor in thecourse of scanning coincides with the image of a particle of foreignmatter disposed in said bottle neck;

(i) circuit means for producing output signals indicating the conditionsof said sensors; and

(j) means -responsive to said output signals for rejecting a bottle fromsaid inspection machine whereby when said output signals indicate thepresence of `foreing matter, the bottle is rejected.

3. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign matter within a. bottle, saiddetection system comprising:

(a) means for directing radiant energy through a bottle;

(b) means for focusing from said radiant energy an image of the bottomof said bottle;

(c) a rotating surface having thereon a reflective segment, said surfacebeing concave and located in the image plane of said bottom of saidbottle as focused by said focusing means;

(d) said refiective segment being arranged to scan said image of saidbottom of said bottle during rotation of saidsurface;

(e) a first radiant energy sensor, said .sensor being disposed in thepath of radiant energy reected from said segment, whereby the amount ofsaid energy re- 'ceived by said segment is momentarily substantiallyvaried whenever said segment in the cour-se of rotation-thereofcoincides with the image of a particle of foreignv matter disposed insaid bottle proximate the bottom thereof;

(f) said rotating surface having a predetermined concavity and beingarranged so that the area proximate the neck of said bottle is focusedby said reflective segment on said surface to an image plane;

(g) said first radiant energy sensor being located in -said image planeof said bottle neck;

(h) means for scanning said bottle neck image by said rst sensor wherebythe amount of radiant energy received by .said first sensor ismomentarily substantially varied whenever said first sensor in thecourse of scanning coincides with the image of a particle of foreignmatter disposed in said bottle neck;

(i) a second radiant energy sensor so located as to sense energytransmitted through the bottom of said bottle;

(j) circuit means for producingoutput signals indicating the conditionsof said sensor; and` (k) means responsive to said output signals forrejecting a bottle from said inspection machine, whereby when saidoutput signals indicate the presence of foreign matter or Iindicates abottle so opaque that foreign matter could not be detected, the bottleis rejected.

4. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign matter within a bottle, said detectionsystem comprising:

(a) means for directing radiant energy through a bottle;

(b) means for focusing from said radiant energy an image of the bottomof said bottle;

(c) a rotating surface having thereon a reflective seg ment, saidsurface being concave and located in the image plane of said bottom ofsaid bottle as focused by said focusing means;

(d) said refiective segment being arranged to scan said image of saidbottom of said bottle during rotation of said surface;

(e) a first radiant energy sensor, said sensor being disposed in thepath of radiant energy reliected from said segment, whereby the amountof said energy received by said segment is momentarily substantiallyvaried whenever said segment in the course of rotation thereof coincideswith the image of a particle of foreign matter disposed in said bottleproximate the bottom thereof;

(f) said rotating surface having a predetermined concavity and beingarranged so that the area proximate the neck of said bottle is focusedby said reective segment on said surface to an image plane;

(g) said first radiant energy sensor being located in said image planeof said bottle neck;

(h) means for scanning said bottle neck image by said rst sensor wherebythe amount of radiant energy received by said first sensor ismomentarily substan tially varied whenever said first sensor in thecourse of scanning coincides with the image of a particle of foreignmatter disposed in said bottle neck;

(i) a second radiant energy sensor so located as to sense energytransmitted through the bottom of said bottle;

(j) circuit means for producing output signals indicating the conditionof said sensors;

(k) means for automatically controlling the gain of the system, wherebyinspection parameters .remain the same for bottles of different opacity;and

(l) means responsive to said output signals for rejecting a bottle fromsaid inspection machine, whereby when said output signal indicates thepresence of foreign matter or indicates a bottle so opaque that foreignmatter could not be detected, the bottle is rejected.

5. A detection system as in claim 4 wherein said reective segment is ofpredetermined shape for linear scanning response.

6. A detection system as in claim 4 wherein said radiant energy sensorsand said gain control means are photocells.

7. In an empty bottle cleanliness inspection machine, a detection systemfor detecting the presence of foreign matter within a bottle at aninspection station, said detection system comprising:

(a) means for directing radiant energy through a bottle at saidinspection station;

(b) a reflecting surface concave on an optical axis disposed in aposition to receive radiant energy passing through said bottle;

(c) means for rotating said reecting surface on an 4axis other than theoptical axis to provide a wobble motion for scanning la bottle neckregion;

(d) means for focusing the image of the bottom of said bottle on saidreliecting surface;

(e) a photocell disposed to receive radiant energy refiected from saidreecting surface;

(f) a non-refiecting line disposed on said -reecting surface, saidrefiecting surface reflecting the received radiation to said photocellwhereby the total amount of said energy received by said reectingsurface is momentarily substantially varied whenever said nonreflectingline in the course of its rotation momentarily coincides with theposition of the image of a particle of foreign matter disposed withinsaid bottle;

(g) said photocell being located with respect to said focusing" meansland said retiecting surface so that said photocell is in the imageplane of said focusing means, as focused by said reflecting surface; and

(h) means for determining the positioning of a bottle relative to saidVinspection station and for providing a signal indicating that the bottleis in said inspection station.

8. The machine of claim 7, said means for directing said radiant energyincluding a light source and lens means. i

9. The machine of claim 7, said rotational and optical axes beingparallel.

10. In an empty bottle cleanliness inspection machine, a detectionsystem for detecting the presence of foreign matter within a bottle atan inspection station, said detection system comprising:

(a) means for directing radiant energy through a bottle atsaidinspection station;

(b) a non-reliecting surface disposed in a position to receive radiantenergy passing through said bottle;

(c) a reflecting line concave on an optical axis disposed on `saidnon-reflecting surface;

(d) means for rotating said surface and line on an axis other than theoptical vaxis to provide a wobble motion for scanning a bottle neckregion;

(e)` means for focusing the image of the bottom of said bottle on saidsurface and line;

(f) a photocell disposed to receive radiant energy 1reflected from saidreflecting line, said reflecting line reecting the received radiation tosaid photocell whereby the total amount of said energy` received by saidreflecting line is momentarily substantially varied whenever said linein the course of its rotation momentarily coincides with the position ofthe image of a particle of foreign matter disposed Within said bottle;

(g) said photocell being located with respect to said focusing means andsaid reflecting line so that said photocell is in the image plane, asfocused by said reecting line, of said focusing means; and

(h) means for determining the position of a bottle relative to saidinspection station and for providing a signal indicating that the bottleis in said inspection station.

11. In an empty bottle cleanliness inspection machine,

a detection system for detecting the presence of foreign matter within abottle at an inspection station, said detection system comprising:

(a) means for directing radiant energy axially through the bottom of abottle at said inspection station;

(b) lens means for receiving radiant energy which has passed throughsaid bottle bottom and for focusing said radiant energy;

(c) a reflective surface concave on an optical axis positionedsubstantially at a focal plane of said lens means, a non-reflecting lineon said reflecting surface;

(d) means for rotating said reecting surface on an axis other than thesaid optical axis to provide a wobble motion for scanning a neck regionof a bottle, said rotational axis being inclined with respect to theaxis defined by said radiant energy means and said lens means;

(e) photocell means in a focal plane of said concave reflecting surfacefor receiving radiation therefrom; and

(f) circuit means connected with said photocell means for producing asignal when the amount of radiant energy received by said photocellmeans is momentarily substantially varied, whereby a signal is generatedwhenever said non-retiecting line in the course of its rotationmomentarily coincides with the position of the image of a yparticle offoreign matter in said bottle.

12. In an empty bottle cleanliness inspection machine,

a detection system for detecting the presence of foreign matter within abottle at an inspection station, said detection system comprising:

(a) means for directing radiant energy through a bottle at saidinspection station;

(b) a reecting element concave on an optical axis disposed in a positionto receive radiant energy passing through said bottle;

(c) a non-rellecting element disposed in the path of light between saidradiant energy directing means and said photocell;

(d) means for rotating said elements including means for rotating saidreflecting element on an axis other than the optical axis to provide awobble motion for scanning a bottle neck region;

(e) means for focusing the image of the bottom of said bottle on saidreliecting element;

(f) a photocell disposed to receive radiant energy reflected from saidreflecting element;

(g) said reflecting element reflecting the received radiation to saidphotocell whereby the total amount of said energy received by saidreflecting element is momentarily subtsantially -varied whenever one ofsaid elements in the course of its rotation momentarily coincides withthe position of the image of a particle of foreign matter disposedwithin said bottle;

(h) one of said elements being substantially a line and the other beinga substantial area relative to said one element; and

(i) said photocell being located with respect to said focusing means andsaid reflecting element so that said photocell is in the image plane, asfocused by said reiiecting element, of said focusing means.

13. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign matter within a bottle, said detectionsystem comprising:

(a) means for directing radiant energy through a bottle;

(b) means for focusing from said radiant energy an image of the bottomof said bottle;

(c) a rotating surface having thereon a reflective segment, said surfacebeing located substantially in the image plane of said bottom of saidbottle as focused by said focusing means;

(d) said reflective segment being arranged to scan said image of saidbottom of said bottle during rotation of said surface; v

(e) a radiant energy sensor, said sensor being dispose in the path ofradiant energy reliected from said segment, whereby the amount of saidenergy received by said segment is monentarily substantially variedwhenever said segment in the course of rotation thereof coincides withthe image of a particle of foreign matter disposed in said bottleproximate the bottom thereof;

(f) said rotating surface being so constructed and arranged so that thearea proximate the neck of said bottle is focused by said reflectivesegment on said surface to an image planeg;

(g) said radiant energy sensor being located in said image plane of saidbottle neck;

(h) means for scanning said bottle neck image by said sensor in suchmanner that in the course of scanning, the image of a particle offoreign matter disposed substantially in the vicinity of said bottleneck will be brought into coincidence with said sensor;

(i) circuit means for producing an output signal indicating thecondition of said sensor; and

(j) means responsive to said output signal for rejecting a bottle fromsaid inspection machine whereby when said output signal indicates thepresence of foreign matter, the bottle is rejected.

14. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign particles within a bottle at aninspection station, said detection system including:

(a) means for directing radiant energy through a bottle at saidinspection station;

(-b) a radiant energy sensor;

(c) radiant energy scanning means for receiving radiant energy passingthrough said bottle;

(c-l) said radiant energy scanning means including non-reflectingrotating means having at least one reflecting segment upon the surfacethereof which is small compared to the entire surface area of saidscanning means;

(d) said reecting segment being so oriented with respect to said bottleas to reflect continuously during inspection the received radiant energyto said radiant energy sensor whereby the intensity of the reflectedradiation to said sensor is momentarily substantially diminished if aparticle of foreign matter is disposed Within said bottle whenever saidsegment in the course of its rotation momentarily coincides with theangular position of the image of said particle; and

(e) circuit means coupled to said sensor for producing a signalindicative of the presence of said particle, only when the intensity ofsaid radiant energy received by said sensor is momentarily substantiallydiminished.

15. In an empty bottle inspection machine, a detection system fordetecting the presence of foreign particles within a bottle, saiddetection system comprising:

(a) means for directing radiant energy through a bottle in an inspectionstation;

(b) a non-reflecting rotating surface having thereon at least onereflecting segment;

(b-1) said reflecting segment being so constructed and arranged as tofocus continuously during inspection an image of the bottle neck portionof said bottle to a predetermined plane;

(c) radiant energy sensing means disposed in the vicinity of said plane;

(d) means for rotating said surface in such a manner as to havesucceeding portions of said image periodically focused upon said sensorwhereby the amount of radiant energy received by said sensor ismomentarily substantially diminished whenever the image of a particle offoreign matter disposed in the 16 vicinity of the neck of said bottlecoincides with the angular position of said sensor;

(e) circuit means for producing output signal indicating the conditionof said sensor; and

(f) means responsive to said output signal for rejecting the bottle fromsaid inspection machine whereby when said output signal indicates thepresence of foreign matter the bottle is rejected.

16. In van empty bottle inspection machine a detection system fordetecting the presence of foreign particles within a bottle, saiddetection system comprising:

(a) means for directing radiant energy through a bottle;

(b) a non-reflecting rotating surface having thereon a reflectivesegment, said reective segment being arranged to focus an image of thearea proximate the neck ofsaid bottle to an image plane;

(c) a radiant energy sensor located substantially in said image plane ofsaid neck of said bottle whereby the amount of said energy received bysaid segment is momentarily substantially diminished whenever saidsensor in the course of scanning coincides with the image of a particleof foreign matter disposed substantially in the vicinity of the neck ofsaid bottle;

(d) circuit means for producing output signal indicating the conditionof said sensor; and

(e) means responsive to the output signal for rejecting the `bottle whensaid output signal indicates the presence of foreign matter.

17. In a detection system as defined in claim 14 wherein said reflectingsegment is a line the width of which is no greater than the largestdimension of the smallest particle to be detected.

References Cited UNITED STATES PATENTS 2,972,812 2/1961 Jackson 250--230X 2,997,598 8/1961 Gramm Z50-230 X 3,191,773 6/1965 Wyman 209-111.?3,283,898 11/1966 Calhoun 88-14 X WALTER STOLW-EIN, Primary Examiner.

U.S."Cl. X.R.

1. IN AN EMPTY BOTTLE INSPECTION MACHINE, A DETECTION SYSTEM FORDETECTING THE PRESENCE OF FOREIGN MATTER WITHIN A BOTTLE, SAID DETECTIONSYSTEM COMPRISING: (A) MEANS FOR DIRECTING RADIANT ENERGY THROUGH ABOTTLE; (B) MEANS FOR FOCUSING FROM SAID RADIANT ENERGY AN IMAGE OF THEBOTTOM OF SAID BOTTLE; (C) A ROTATING SURFACE HAVING THEREON AREFLECTIVE SEGMENT, SAID SURFACE BEING CONCAVE AND LOCATED IN THE IMAGEPLANE OF SAID BOTTOM OF SAID BOTTLE AS FOCUSED BY SAID FOCUSING MEANS;(D) SAID REFLECTIVE SEGMENT BEING ARRANGED TO SCAN SAID IMAGE OF SAIDBOTTOM OF SAID BOTTLE DURING ROTATION OF SAID SURFACE; (E) A RADIANTENERGY SENSOR, SAID SENSOR BEING DISPOSED IN THE PATH OF RADIANT ENERGYREFLECTED FROM SAID SEGMENT, WHEREBY THE AMOUNT OF SAID ENERGY RECEIVEDBY SAID SEGMENT IS MOMENTARILY SUBSTANTIALLY VARIED WHENEVER SAIDSEGMENT IN THE COURSE OF ROTATION THEREOF COINCIDES WITH THE IMAGE OF APARTICLE OF FOREIGN MATTER DISPOSED IN SAID BOTTLE PROXIMATE THE BOTTOMTHEREOF; (F) SAID ROTATING SURFACE HAVING A PREDETERMINED CONCAVITY ANDBEING ARRANGED TO THAT THE AREA PROXIMATE THE NECK OF SAID BOTTLE ISFOCUSED BY SAID REFLECTIVE SEGMENT ON SAID SURFACE TO AN IMAGE PLANE;(G) SAID RADIANT ENERGY SENSOR BEING LOCATED IN SAID IMAGE PLANE OF SAIDBOTTLE NECK; (H) MEANS FOR SCANNING SAID BOTTLE NECK IMAGE BY SAIDSENSOR WHEREBY THE AMODUNT OF RADIANT ENERGY RECEIVED BY SAID SENSOR ISMOMENTARILY SUBSTANTIALLY VARIED WHENEVER SAID SENSOR IN THE COURSE OFSCANNING COINCIDES WITH THE IMAGE OF A PARTICLE OF FOREIGN MATTERDISPOSED IN SAID BOTTLE NECK; (I) CIRCUIT MEANS FOR PRODUCING AN OUTPUTSIGNAL INDICATING THE CONDITION OF SAID SENSOR; AND (J) MEANS RESPONSIVETO SAID OUTPUT SIGNAL FOR REJECTING A BOTTLE FROM SAID INSPECTIONMACHINE WHEREBY WHEN SAID OUTPUT SIGNAL INDICATES THE PRESENCE OFFOREIGN MATTER, THE BOTTLE IS REJECTED.